2.04

我们创建一个大数类，数据初始化为0，在我们进入这个页面时就会直接计算出来。

private void initData() {
        list=new ArrayList<>();
        SQLiteDatabase db=helper.getReadableDatabase();
        Cursor cursor=db.query("account2",null,"Date like '"+month11+"%'",null,null,
                null,null);
        BigDecimal sum=new BigDecimal(0);
        while (cursor.moveToNext()){
            costList clist=new costList();//构造实例
            BigDecimal temp=new BigDecimal(cursor.getString(cursor.getColumnIndex("Money")));
            sum=sum.add(temp);
            clist.setSe(cursor.getString(cursor.getColumnIndex("Se")));
            clist.set_id(cursor.getString(cursor.getColumnIndex("_id")));
            clist.setTitle(cursor.getString(cursor.getColumnIndex("Title")));
            clist.setDate(cursor.getString(cursor.getColumnIndex("Date")));
            clist.setMoney(temp.toString());
            list.add(clist);
        }
        //绑定适配器
        listAdapter=new ListAdapter(this,list);
        listView.setAdapter(listAdapter);
        textView.setText(sum.toString());
        db.close();
    }